Uglegorsk is a coastal port town and the administrative center of Uglegorsky District in Sakhalin Oblast, Russia, located on the west coast of Sakhalin Island, 277 kilometers (172 mi) northwest of Yuzhno-Sakhalinsk, the administrative center of the oblast. Population: 10,381 (2010 census); 13,396 (2002 census); 18,402 (1989 Soviet census).